Finnish smartphone startup Jolla has announced today that their Sailfish OS has exited beta and is almost ready for installation on Android devices, aimed at the market of fans who like to install custom ROMs on their smartphones and tablets.

The Jolla has been available in Europe for a couple of months, but there has been no carrier or OEM support except for small Finnish carrier DNA. Moving forward, Jolla says it is looking to extend online sales to Russia, India and Hong Kong while negotiating "new channels" in Europe.

Version 1.0 of the Sailfish OS will be available to install on Android devices starting on March 1st, and the company says active developers have already ported the beta to some Galaxy, Nexus and Xperia phones.

"Last year in China alone, about 100 million devices were re-flashed after the purchase with a new operating system. This approach allows Sailfish OS to scale into volume fast without limitations. This is a scaling opportunity in a similar way as we have seen in the mobile gaming industry recently," Antti Saarnio, chairman of Jolla's board noted, showing a clear strategy aimed at China.

I think what you are missing, Jemborg, is that Sailfish is Android-compatible, but has a significantly different GUI. The Wiki entry has a few rough English bits, but does imply that at least some, if not all Android apps will be natively compatible. The WIki states that MOST programs work fine, but a few that use non-Android standards do not, and also some programs will run faster if ported over. This also means that you can install Sailfish on any Android-based device, theoretically, at least, with little to no individual-device customization, from what I can gather (I could be wrong on the customization bit).

Another very significant difference from Android, is that Sailfish is NOT PRISM-accessible, both by design, and by the fact that that Jolla's servers are not in the US. The NSA currently has access to all Android and iOS metadata, and in some cases direct data.

Sailfish is also fully open-source, which avoids the increasing closed nature of the Google Apps system.